Goldie is a series of flexible open-source parsing tools, including a D2
library called GoldieLib. It's compatible with GOLD Parser Builder and can
be used together with it, but does not require it. In fact, Goldie can be
used as a cross-platform, shell-scripting-compatible alternative to GOLD
Parser Builder.
== Links: ==
Main homepage and documentation:
http://www.semitwist.com/goldie/
Prepackaged downloads:
http://www.dsource.org/projects/goldie/browser/downloads
The related GOLD Parser Builder:
http://www.devincook.com/goldparser/
== New in v0.4: ==
- Switched from D1/Tango to D2/Phobos.
- New tool: GRMC: Grammar Compiler. Because of this, Goldie no longer
requires GOLD Parser Builder.
- Grammars can be compiled not only from GRMC: Grammar Compiler, but
also through the D API, GoldieLib.
- No longer requires xfBuild or Rebuild.
- Executable filenames are now prefixed with 'goldie-' to minimize
chance of collisions on the PATH.
- Many misc changes/improvements to tools, API and documentation.
- Includes a lexing-only D2 grammar:
http://www.dsource.org/projects/goldie/browser/trunk/lang/dlex.grm
This D2 grammar does have a few small limitations ATM though, which I've
already described here:
http://www.mail-archive.com/digitalmars-d-learn puremagic.com/msg11491.html
http://www.mail-archive.com/digitalmars-d-learn puremagic.com/msg11493.html
== Some of Goldie's benefits: (most are thanks to Goldie's compatibility
with GOLD Parser Builder) ==
- Grammars are fully-reusable: No need to create a new grammar for every
use and every host language. Many grammars are already available.
- Grammar-agnostic engine: One lexer/parser engine can be used for all
grammars.
- Engines for nearly any language or platform: A cross-platform D v2.x
engine is included via GoldieLib. Engines for many other platforms are also
available. New engines are easy to write.
- Dynamic-Style: Dynamic-style lets you write programs that support
user-created grammars.
- Static-Style: Static-style provides compile-time checks and extra
type-safety.
- Lexing and parsing: Lexing and parsing are defined in the same file
and handled by one unified tool.
- Many tools available.
Goldie is fully-usable and has been tested on both Windows and Linux (it
should also work on OSX and any other platform supported by DMD, but has not
been tested), although GoldieLib's API is still subject to change. Goldie is
licensed under The zlib/libpng License.

I try use the gold from trunk, not the release version . It seems
very slow for parse css . please see this
http://www.dsource.org/projects/goldie/ticket/18 .
Is all lalr slow like this , or it is a gold problem .
On Sun, Mar 27, 2011 at 4:11 PM, Nick Sabalausky <a a.a> wrote:

Goldie is a series of flexible open-source parsing tools, including a D2
library called GoldieLib. It's compatible with GOLD Parser Builder and ca=

type-safety.
=A0 =A0- Lexing and parsing: Lexing and parsing are defined in the same f=

ile

and handled by one unified tool.
=A0 =A0- Many tools available.
Goldie is fully-usable and has been tested on both Windows and Linux (it
should also work on OSX and any other platform supported by DMD, but has =

not

been tested), although GoldieLib's API is still subject to change. Goldie=

For other people who haven't read my reply to that ticket, this is the top
priority for Goldie now. I've profiled, and the biggest bottleneck by far is
the (rather stupid and half-assed) way that I'm handling character sets in
the lexer. (To directly answer the quesion, it's neither an LALR thing nor a
GOLD thing, it's just a temporary Goldie thing.)
Additionally, my plain is to switch from large infrequent releases to
smaller more frequent releases, so it shouldn't be another 6+ month wait for
"v0.5 with a speed boost". This v0.4 version has a lot of big stuff in it
(the change from D1->D2 and the grammar compiler), so that's why it took so
long.

So could your library be used to implement an alternative for HTOD? Or
more simply put, could I use this to do (simple) transformations of C
code?

C code is admittedly a bit tricky because it uses a preprocessor. But in
general, yes, Goldie can be used transform source. The way it would work is
like this:
1. Define a grammar for the "input" language.
There's an ANSI C grammar here, but I haven't looked at it, so I don't know
how good it is:
http://www.devincook.com/goldparser/grammars/index.htm
An introduction to the grammar description langauge is here:
http://www.semitwist.com/goldie/Start/Grammar/
2. Use Goldie to parse the input. Details here:
http://www.semitwist.com/goldie/Start/HowToUse/
3. Once Goldie's parsed the input, it will give you a parse tree (it'll be
structured based on the grammar you used). You can then walk the tree and do
whatever you want with it. I don't recommend actually modifying the parse
tree that Goldie gives you in-place, since the interface isn't really
designed for that right now (though you may still be able to make it work).
But you can walk it and either build up your own tree structure, or convert
it to text however you want, etc.
Actually, you can even take a look at what the parse tree you'll get back
will look like before writing any code: Use the included Goldie parse (
http://www.semitwist.com/goldie/Tools/Parse/ ) to parse a file according to
whatever grammar you want to use. It'll save the parse tree to JSON. Then
you can inspect the parse tree with this: (
http://www.semitwist.com/goldie/Tools/JsonViewer/ ). But try to use just a
small sample file: Parse trees tend to get very big, very fast and
JsonViewer is written in C# and can't handle large files very well.
Since you're talking about C, you'll probably want to run your original C
code through the "preprocess-only" option of a real C compiler. (I *think*
DMC will do that.) Then parse the resulting "preprocessed C" files with
Goldie. (Although if your goal is an HTOD-like tool, maybe you would need to
deal with the original un-preprocessed source directly. If Golde's grammar
langauge doesn't seem quite up to the task, it probably wouldn't bee too
hard to just manually make a basic C preprocessor.)
Right now, the grammar description format isn't really very good as
describing preprocessors (a limitation Goldie inherited from GOLD Parser
Builder). But fixing that limitation is one of the things on my TODO list
for Goldie.
If you do try this, I'd love to hear how it works out :) Even if you
encounter any problems, it would be very helpful for me to know. Haven't
gotten a whole lot of feedback yet.

Since you're talking about C, you'll probably want to run your original C
code through the "preprocess-only" option of a real C compiler. (I *think*
DMC will do that.) Then parse the resulting "preprocessed C" files with
Goldie. (Although if your goal is an HTOD-like tool, maybe you would need to
deal with the original un-preprocessed source directly.

Why? Just call the preprocessor from your tool or from a wrapping script
and go on with the preprocessed C code. Should be much easier and more
compatible because C compilers ought to know how to preprocess correctly.
For GCC the option you're looking for is "-E", btw.

If Golde's grammar
langauge doesn't seem quite up to the task, it probably wouldn't bee too
hard to just manually make a basic C preprocessor.)

Since you're talking about C, you'll probably want to run your original C
code through the "preprocess-only" option of a real C compiler. (I
*think*
DMC will do that.) Then parse the resulting "preprocessed C" files with
Goldie. (Although if your goal is an HTOD-like tool, maybe you would need
to
deal with the original un-preprocessed source directly.

Why? Just call the preprocessor from your tool or from a wrapping script
and go on with the preprocessed C code. Should be much easier and more
compatible because C compilers ought to know how to preprocess correctly.
For GCC the option you're looking for is "-E", btw.

If by "your tool" mean a program that uses Goldie to process C code, then
yea, that's what I meant.
If you meant that Goldie should invoke a C preprocessor directly, that's a
bit tricky: Goldie is a generalized parsing tool (sort of like ANTLR or
Spirit), so it doesn't really know "Ok, this is supposed to be C". It just
parses according to whatever grammar it's given. Of course, it's not
entirely out of the question to have some sort of system for specifying that
a source should have XYZ tool (such as "C preprocessor") invoked on it
first, etc, but it's probably easiest if programs using Goldie just invoke
whatever other tools they need by themselves.
(Sorry if I've stil misunderstood - it's late over here ;) )

Since you're talking about C, you'll probably want to run your original C
code through the "preprocess-only" option of a real C compiler. (I
*think*
DMC will do that.) Then parse the resulting "preprocessed C" files with
Goldie. (Although if your goal is an HTOD-like tool, maybe you would need
to
deal with the original un-preprocessed source directly.

Why? Just call the preprocessor from your tool or from a wrapping script
and go on with the preprocessed C code. Should be much easier and more
compatible because C compilers ought to know how to preprocess correctly.
For GCC the option you're looking for is "-E", btw.

If by "your tool" mean a program that uses Goldie to process C code, then
yea, that's what I meant.

I've used your tool yesterday. I used it on a simple C file with the
ANSI C grammar from the gold website. It does seem to work fine, but
yeah I have to preprocess a C file first (I've spent so much time with
D that I almost completely forgot about the C preprocessor in the
first place).
I've tried a file with your ParseAnything sample. It works ok as long
as all the types are defined. If not I usually get a Token exception
of some sort. Is this considered the semantic pass stage?
Btw, is there a grammar file for C99? What about C++, I haven't seen a
grammar on the Gold website? (well, C++ is a monster, I know..).
I'm also trying to figure out whether to go with the static or dynamic
approach (I've looked at your docs). The static examples seem quite
complex, but perhaps they're more reliable. I think I'll do a few
tryouts with dynamic style since it looks much easier to do. If I get
anything done you'll know about it. :)

I've used your tool yesterday. I used it on a simple C file with the
ANSI C grammar from the gold website. It does seem to work fine, but
yeah I have to preprocess a C file first (I've spent so much time with
D that I almost completely forgot about the C preprocessor in the
first place).
I've tried a file with your ParseAnything sample. It works ok as long
as all the types are defined. If not I usually get a Token exception
of some sort. Is this considered the semantic pass stage?

Like any generalized parsing tool (AFAIK), Goldie doesn't really have a
semantic stage (because language semantics isn't something that's easily
formalized).
Probably the C grammar just considers something in your source to be either
a syntax or grammatical error. (This could be a bug or limitation in the C
grammar.) Goldie currently handles syntax/grammatical errors by throwing a
ParseException when it detects all the errors it can find. The message of
the exception is the "filename(line:col): Error: Description of error"
message that you'd normally expect a compiler to output. Most of the apps in
Goldie catch this exception and just output the message, but I guess I
didn't do that in ParseAnything.
Of course, it could also be a bug in either ParseAnything or Goldie. Can you
send one of the C files that's getting an error? I'll take a look and see
what's going on.
You may want to try "goldie-parse" instead of "goldie-parseAnything" (I
really should rename one of them, it's probably confusing).
"goldie-parseAnything" is mainly intended as an example of how to use Goldie
(like the Calculator examples). "goldie-parse" is the one that outputs JSON.

Btw, is there a grammar file for C99? What about C++, I haven't seen a
grammar on the Gold website? (well, C++ is a monster, I know..).

Not that I'm aware of. But if you know the differences between ANSI C and
C99 you should be able to modify the ANSI C grammar and turn it into a C99.
The grammar description language should be very easy to understand if you're
familiar with BNF and regex (In fact, the grammar definition langauge
doesn't even use the barely-readable Perl regex syntax - it uses a far more
readable equivalent instead). BTW, Tip on the grammar language: Everything
enclosed in angle brackets is a nonterminal.
And yea, C++ is a beast. And one of C++'s biggest issues is that, not only
does it have the preprocessor, but what's worse: the parsing is dependent on
the semantics pass. I'd say that any generalized parsing tool that can do
C++ properly is doing an *incredibly* damn good job.

I'm also trying to figure out whether to go with the static or dynamic
approach (I've looked at your docs). The static examples seem quite
complex, but perhaps they're more reliable. I think I'll do a few
tryouts with dynamic style since it looks much easier to do.

The general recommendation is to use static whenever you just have one
specific grammar you're trying to deal with (because it provides better
protection against mistakes). But you're right, the dynamic style may be an
easier way to learn Goldie.
If you haven't already, you may wat to look at the source for the calculator
examples. They're both the exact same program, but one does it the static
way, and the other does it the dynamic way.

I'm not at my computer right now, so I can't check, but it sounds like the
grammar follows the really old C-style of requiring structs to be declared with
"struct StructName varName". Apperently it doesn't take into account the
possibility of typedefs being used to eliminate that. When I get home, I'll
check, I think it may be an easy change to the grammar.

I'm not at my computer right now, so I can't check, but it sounds like the
grammar follows the really old C-style of requiring structs to be declared
with "struct StructName varName". Apperently it doesn't take into account
the possibility of typedefs being used to eliminate that. When I get home,
I'll check, I think it may be an easy change to the grammar.

Yea, turns out that grammar just doesn't support using user-defined types
without preceding them with "struct", "union", or "enum". You can see that
here:
<Var Decl> ::= <Mod> <Type> <Var> <Var List> ';'
| <Type> <Var> <Var List> ';'
| <Mod> <Var> <Var List> ';'
<Mod> ::= extern
| static
| register
| auto
| volatile
| const
<Type> ::= <Base> <Pointers>
<Base> ::= <Sign> <Scalar> ! Ie, the built-ins like char, signed int,
etc...
| struct Id
| struct '{' <Struct Def> '}'
| union Id
| union '{' <Struct Def> '}'
| enum Id
So when you use "MyType" instead of "struct MyType": It sees "MyType",
assumes it's a variable since it doesn't match any of the <Type> forms
above, and then barfs on "var" because "variable1 variable2" isn't valid C
code. Normally, you'd just add another form to <Base> (Ie, add a line after
" | enum Id" that says " | Id "). Except, the problem is...
C is notorious for types and variables being ambiguous with each other. So
the distinction pretty much has to be done in the semantic phase (ie,
outside of the formal grammar). But this grammar seems to be trying to make
that distinction anyway. So trying to fix it by just simply adding a "<Base>
::= Id" leads to ambiguity problems with types versus variables/expressions.
That's probably why they didn't enhance the grammar that far - their
"separation of type and variable" approach doesn't really work for C.
I'll have to think a bit on how best to adjust it. You can also check the
GOLD mailing lists here to see if anyone has another C grammar:
http://www.devincook.com/goldparser/contact.htm

As I understand, <Type> is a type, <Var> is a variable. There should be no
problem here.

First of all, the name <Var> up there is misleading. That only refers the
the "name of the variable" in the variable's declaration. When actually
*using* a variable, that's a <Value>, which is defined like this:
<Value> ::= OctLiteral
| HexLiteral
| DecLiteral
| StringLiteral
| CharLiteral
| FloatLiteral
| Id '(' <Expr> ')' ! Function call
| Id '(' ')' ! Function call
| Id ! Use a variable
| '(' <Expr> ')'
So we have a situation like this:
<Type> ::= <Base>
<Base> ::= Id
<Value> ::= Id
So when the parser encounters an Id, how does it know whether to reduce it
to a <Base> or a <Value>? Since they can both appear in the same place (Ex:
Immediately after a left curly-brace, such as at the start of a function
body), there's no way to tell.
Worse, suppose it comes across this:
x*y
If x is a variable, then that's a multiplication. If x is a type then it's a
pointer declaration. Is it supposed to be multiplication or a declaration?
Could be either. They're both permitted in the same place.

As I understand, <Type> is a type, <Var> is a variable. There should be
no problem here.

First of all, the name <Var> up there is misleading. That only refers the
the "name of the variable" in the variable's declaration. When actually
*using* a variable, that's a <Value>, which is defined like this:
<Value> ::= OctLiteral
| HexLiteral
| DecLiteral
| StringLiteral
| CharLiteral
| FloatLiteral
| Id '(' <Expr> ')' ! Function call
| Id '(' ')' ! Function call
| Id ! Use a variable
| '(' <Expr> ')'
So we have a situation like this:
<Type> ::= <Base>
<Base> ::= Id
<Value> ::= Id
So when the parser encounters an Id, how does it know whether to reduce it
to a <Base> or a <Value>? Since they can both appear in the same place
(Ex: Immediately after a left curly-brace, such as at the start of a
function body), there's no way to tell.
Worse, suppose it comes across this:
x*y
If x is a variable, then that's a multiplication. If x is a type then it's
a pointer declaration. Is it supposed to be multiplication or a
declaration? Could be either. They're both permitted in the same place.

In other words, we basically have a form of this:
<A> ::= <B> | <C>
<B> ::= X
<C> ::= X
Can't be done. No way to tell if X is <B> or <C>.

I'm not at my computer right now, so I can't check, but it sounds like
the grammar follows the really old C-style of requiring structs to be
declared with "struct StructName varName". Apperently it doesn't take
into account the possibility of typedefs being used to eliminate that.
When I get home, I'll check, I think it may be an easy change to the
grammar.

Yea, turns out that grammar just doesn't support using user-defined types
without preceding them with "struct", "union", or "enum". You can see that
here:
<Var Decl> ::= <Mod> <Type> <Var> <Var List> ';'
| <Type> <Var> <Var List> ';'
| <Mod> <Var> <Var List> ';'
<Mod> ::= extern
| static
| register
| auto
| volatile
| const
<Type> ::= <Base> <Pointers>
<Base> ::= <Sign> <Scalar> ! Ie, the built-ins like char, signed int,
etc...
| struct Id
| struct '{' <Struct Def> '}'
| union Id
| union '{' <Struct Def> '}'
| enum Id
So when you use "MyType" instead of "struct MyType": It sees "MyType",
assumes it's a variable since it doesn't match any of the <Type> forms
above, and then barfs on "var" because "variable1 variable2" isn't valid C
code. Normally, you'd just add another form to <Base> (Ie, add a line
after " | enum Id" that says " | Id "). Except, the problem is...
C is notorious for types and variables being ambiguous with each other. So
the distinction pretty much has to be done in the semantic phase (ie,
outside of the formal grammar). But this grammar seems to be trying to
make that distinction anyway. So trying to fix it by just simply adding a
"<Base> ::= Id" leads to ambiguity problems with types versus
variables/expressions. That's probably why they didn't enhance the grammar
that far - their "separation of type and variable" approach doesn't really
work for C.
I'll have to think a bit on how best to adjust it. You can also check the
GOLD mailing lists here to see if anyone has another C grammar:
http://www.devincook.com/goldparser/contact.htm

Unfortunately, I think this may require LALR(k). Goldie and GOLD are only
LALR(1) right now.
I had been under the impression that LALR(1) was sufficient because
according to the oh-so-useful-in-the-real-world formal literature, any LR(k)
can *technically* be converted into a *cough* "equivalent" LR(1). But not
only is algorithm to do this hidden behind the academic ivory wall, but word
on the street is that the resulting grammar is gigantic and bears little or
no resemblance to the original structure (and is therefore essentially
useless in the real world).
Seems I'm gonna have to add some backtracking or stack-cloning to Goldie,
probably along with some sort of cycle-detection. (I think I'm starting to
understand why Walter said he doesn't like to bother with parser generators,
unngh...)

just read you replay, very look forward to the Character Set Optimization.
and thank you to done such a useful project .
On 3/27/11, Long Chang <changlong jkys.info> wrote:

I try use the gold from trunk, not the release version . It seems
very slow for parse css . please see this
http://www.dsource.org/projects/goldie/ticket/18 .
Is all lalr slow like this , or it is a gold problem .
On Sun, Mar 27, 2011 at 4:11 PM, Nick Sabalausky <a a.a> wrote:

Goldie is a series of flexible open-source parsing tools, including a D2
library called GoldieLib. It's compatible with GOLD Parser Builder and
can
be used together with it, but does not require it. In fact, Goldie can b=

type-safety.
=A0 =A0- Lexing and parsing: Lexing and parsing are defined in the same =

file

and handled by one unified tool.
=A0 =A0- Many tools available.
Goldie is fully-usable and has been tested on both Windows and Linux (it
should also work on OSX and any other platform supported by DMD, but has
not
been tested), although GoldieLib's API is still subject to change. Goldi=